Consisting of documents detailing the 1785 travels and observations of Joseph Hadfield through the Northwest fur trade of North America and to Niagara Falls (probably written after 1810). Observations are primarily economic in nature; however, there are also references to the geographical and cultural surroundings.

The fonds consists primarily of Logan's scientific work. A small percentage relates to the affairs of his family and to memorials to Logan after his death. The great majority of the papers consists of scientific correspondence from about 1820 to 1874, but mostly for the years following his appointment to the Survey in 1842. The letters deal with the collection, exchange and description of geological specimens, expeditions under the aegis of the survey, problems of research and scientific interpretation, scientific meetings, and visits by scientists. The number of correspondents, both individuals and learned societies, is very large, but the most substantial bodies of letters are from J.W. Dawson, geologist and Principal of McGill University, James Hall, paleontologist of the New York Geological Survey, Alexander Murray, Logan's chief assistant, and James Lowe of Grenville, Québec, who supplied Logan with specimens and appears to have been casually employed by him on surveying jobs and field trips. Other correspondents include Sanford Fleming, E.D. Ashe of the Québec Observatory, Thomas Sterry Hunt, and R.I. Murchison of the Geographical Society of Great Britain. Some letters pertain to political or social affairs, but usually in close connection with the scientific work of Logan or the Survey. These files contain copies of some of Logan's outgoing letters, as well as some letters addressed to other individuals, generally his assistants. Other scientific papers consist of field trip records (a journal kept during an expedition in 1845, a weather table kept on Lake Superior in the winter of 1846-1847, work records and astronomical readings for surveying projects, notes on mineral deposits, and lists of specimens), manuscripts of three scientific papers, as well as "Observations on the proposed Geological Survey", and manuscript and printed maps and geological schemata, including some by Logan of the Bay of Fundy, Labrador, and Hamilton, Ontario regions. Manuscript catalogues of specimens were prepared by Logan for the Paris Exhibitions of 1855 and 1867. Official reports include Logan's annual reports for 1842-1844, an overview of the work of the Geological Survey, 1866, two reports by Logan on prospects for mining on the north shore of Lake Superior, 1846, 1847, and one on mineral deposits around Rivière-du-Loup, 1853, as well as Logan's copy of his proposed Geological Survey Bill, 1844, and some copies of reports on mining and cartography prepared by others. Logan's financial records include expense accounts for Geological Survey expeditions, as well as other professional expenditures, such as books. His private and family life is reflected by a very brief diary of an Atlantic crossing in 1856, letters to and from his brothers James and Henry, his father, his uncle Hart Logan, and Hart Logan's partner John Fleming, covering the years 1772-1856. There are also baptismal and burial certificates, and legal documents, particularly bills of sale pertaining to James Logan's farm. Memorials to Logan after his death include J.W. Dawson's correspondence concerning the Logan Memorial Fund and Collection, 1881, and a manuscript biography by Alexander Murray. There is a chronological and author/recipient index to these papers.

Additional materials received from McGill Library's Rare Books and Special Collections consist of correspondence, 1837-1871; notices of admission to scientific and historical societies, 1842-1867; a history of the geological survey 1850; a report on mining locations addressed to B. Papineau, 1847; and correspondence with Robert Bell, 1861-1874.

Fonds consists of a travel journal from a trip to Italy kept by Duboille.

Very few of the McLeod papers actually concern the Observatory. However, his work for the railways and in Newfoundland is documented, as are his views on the education and employment of engineers. The basic record for the early part of his career is a diary kept from 1870 to 1875, regarding student days and early work on the Observatory. An essay, "Winter under canvas" (1868) describes an early surveying job, and a letter from his father (1872) inquires about his academic progress. His work for the railways is documented by three letters of recommendation, and two letters (one from Stanford Fleming) on the work of his colleagues in the West. The Newfoundland survey (1875) is described in McLeod's diary, a manuscript essay "Across Newfoundland" (1876), his printed reports and three letters. His work at McGill is represented by six letters (largely official acknowledgements of appointments), and McLeod's manuscript notes on McGill history. McLeod's concern with the engineering profession is reflected in two addresses on education and professional development, and copies of about a dozen letters to Sir Wilfrid Laurier (1906-1908), C.A. McGrath and E.F. Wurtele (1912), largely on the employment of engineers in the civil service.

This diary written at Rome, 1848-1855, is in English, French and Italian.

Diaries with gaps for the years 1868 to 1910. Also included are a diary of a trip to Scotland and England in 1862 and a scrapbook which covers the years 1863-1869 as well as a catalogue of Wicksteed's library.

Madame Desrivière's diaries describe social, family and economic life in Montréal and Stansbridge, Québec. The first (1843-1846) and last (1853-1854) volumes are in French, the others in English.

Andreassen's papers fall into three series: personal materials, diaries, and professional files. Personal materials include family correspondence, 1929-ca 1932, and ca 30 cm of class notes and draft papers stemming from his student years, largely at Louisiana State. There are also files of private correspondence, some addressed to Mrs Andreassen, from the period 1975-1980. Andreassen's diaries cover the years 1936-1940, 1945-1952, 1962-1965, and 1968-1976. They record the working day and are interleaved with memoranda and correspondence, often of a personal nature. Professional files vary in nature with each stage of Andreassen's career, but correspondence and reports are consistent elements. To these may be added copies of surveys and inventories of the Louisiana Historical Records Survey, expense accounts and photographs arising from his work for UNRRA, records of archival deposits and drafts on an institutional history prepared as Archivist of CNR, and annual reports written as McGill Archivist.

The fonds documents A.D. Blackader's personal and professional life. The fonds contains correspondence, diaries, autobiographical notes, papers and lectures, certificates, diplomas, testimonials, article reprints, photographs, and some memorabilia.